Piccardi
{{PatentInfo |Inventor=Edward G. Knight |Assignee=Thomas De La Rue and Company |Country=GB |ApplicationNum=30504/37 |ApplicationDate=1937-11-06 |PatentNum=497169 |PatentDate=1938-12-14 |PriorityDate=1937-11-06 |Titolo=Improvements in or relating to fou...